12v computing

Discussion in 'Motorhome Chat' started by mlp, Jun 19, 2008.

  1. mlp

    mlp Deleted User

    Hi all,

    New to the site and to mobile homes, so please forgive any realy stupid questions.

    I'm a computer programmer and so would like a resonably powerfull machine, my question is has any one used a 12v psu in there mobile home? something like this;

    PW-200-M 200W DC-DC Mini ITX ATX 12V Power Supply PSU - eBay (item 170228369291 end time Jun-18-08 18:00:00 PDT)

    The linked psu is not rated for a car (because i guess of the drain from the starter effecting the voltage) would this matter if it was attached to a 2nd leasure battery?

    I know I could use an inverter but feel the conversion from 12v upto 240v and back down would produce heat and use valuble power. Any advice would be greatfully accepted.

    Cheers Mark
  2. artona


    Jul 31, 2007
    Likes Received:
    Hi Mark

    I am a photographer and we use a powerful laptop and a very fast dye sub printer for event photography. We do have a generator but prefer an inverter linked direct to leisure batteries. They are often working all day without problems

  3. Thepips

    Thepips Trade Member

    Sep 26, 2007
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    The power supply you found isn't regulated so I wouldn't recommend it, putting 14v straight onto your motherboard would not do the components much good! If your pc uses laptop components (they run off the 5v rail) then it might work, as the 5v should be regulated by the PSU.
    I've got a 12v pc installed on my RV but I elected to go the low power route and use Epia motherboard, 2.5 inch hard drive and slot DVD reader. For power I'm using the M2-ATX although currently I'm not taking advantage of all the features. It's my intent to connect it up to a switched supply so it'll restart automatically when I turn the ignition on. Again, to save power I use a USB TV Tuner and 3G modem (they only draw 500 milliamps each).
    The PC is connected to the TV and when I get my touchscreen back from the repairers will do double duty as Navigation screen and rearview camera.
    Yes, of course you could go with a laptop or use the standard PSU and inverter but it wouldn't be as much fun would it?

    Last edited: Jun 19, 2008
  4. olley

    olley Funster

    Jul 29, 2007
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  5. Wildman

    Wildman Read Only Funster

    May 30, 2008
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    Ilfracombe, Devon
    Hi, I don't see a problem running it. It would work fine. Depending in current consumption a 120 amp/hr battery would probably only last about 3 hours allowing a 50% safety factor on the battery. How are you going to replace that charge, sufficient solar panels would cost you about £1000, and fuel for genny is expencive. So provided you are prepared to pay the cost of recharging go for it, other wise use a laptop and restrict useage. Keep main computer for on site with 240v hookup.Do let us know how you get on.
  6. mlp

    mlp Deleted User

    Hi all, thanks for the replies.

    Doug, Wildman has gotten me a bit worried about power consumption - 3 hours is hardly enough to time, Can you give me some idea of how long your system runs - as it's similar to what i have in mind.
    I have a sony viao that runs 7 hours on it's own battery (I'm planning to mount that in the cab and have a 12v cigar adaptor for it) , unfortunately it only has a 10" screen.

    What i want as a main machine would be a Duo based machine running 2 18" monitors. I'm a flash designer and need the screen real-estate (honest! ;) I'm planning to wild camp and would like to keep the power consumption down. I have 2 old 12v tft's that I doubt will draw much more than 60w but I have no idea of the power consumption of a Duo motherboard.

    Given that the MB draws 160w (guessing here) and 60w for the monitors how long would a 120 amp/hr battery last?
  7. GJH

    GJH Funster Life Member

    Aug 20, 2007
    Likes Received:
    Acklam, Teesside, originally Glossop
    Pretty simple maths:
    160w + 60w = 220w.
    220w/12v = 18a
    120ah/18a = 6.7 hours

    i.e. just what Wildman said - "a 120 amp/hr battery would probably only last about 3 hours allowing a 50% safety factor on the battery".

    Not really the thing for wild camping because of the problem of (as Wildman said) replacing the power used.

  8. mlp

    mlp Deleted User

    Pretty simple when you know, should have paid attention in physics...

    6 hours on a 120Ah battery - this might need some re-thinking :Eeek:

    just checked the battery on my laptop, 4400mAh so the whole thing runs for 6-7 hours on 4.4Ah so that would be practaly a week on a 120Ah battery.

    Will have to look into useing a laptop MB and CPU.

    Thanks Mark
  9. JayDee

    JayDee Funster

    Oct 7, 2007
    Likes Received:
    N. Devon
    I'm going to avoid all the technical stuff, coz I'm not sure I'm completely comfortable with it.
    Suffice to say that with fairly heavy usage of the laptop through a dedicated selectable output transformer from (I think I've got the name right) Action Replay, I needed Geo to help me start up, having flattened my vehicle battery:Doh: - I used the laptop to store music, now on a 250GB laptop harddrive (£60 quid from Amazon) and it probably got about 10 hours of play over the course of the weekend.
    Then be damned if the next time I nearly flattened the leisure battery doing the same:Doh::Eeek::Doh:.
    So I've learned my lesson and am getting a freestanding 60watt solar panel next month. That should sort it -

    or not.:BigGrin:


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